Using DAQ generate a 38kHz on an analog output on and off for ms using labVIEW

I wish to generate a 38kHz pulse on an analog output of a mydaq to drive a infrared led. The 38kHz signal is not continuous but is on for 1ms and off for 1ms.

Hi pat,
you generate a waveform using 38kHz as sample rate and a rectangular shape of 1ms HIGH level and 1ms LOW level. Using some simple math you will notice you need 38 samples at 38Khz to output a value for 1ms…
Then you just output that waveform on a AO channel.
Best regards,
GerdW
CLAD, using 2009SP1 + LV2011SP1 + LV2014SP1 on WinXP+Win7+cRIO
Kudos are welcome

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How do I use the NI 9481 to switch a load on for 30s and off for 30s?

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Hi M.Fish and welcome to the NI Discussion Forums!
Try looking at this forum post as it may lead you in the right direction. http://forums.ni.com/ni/board/message?board.id=70&message.id=7113&requireLogin=False
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High Noise on Analog Output PCI 6289

Hi guys
I am using a PCI 6289 M series device for A/D characterization , I am using the device both for the analog output generation and also for data acquistion of the digital lines , The dynamic tests for the A/D were showing a very poor SNR ratio of the ADC, it is a 12 bit adc so technically in the ideal case i should atleast see 90 db but the resulting figure was way lower around 40 db .
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Hi Tom
Thanks a lot for responding to the thread , did not expect a response in the holiday season . The SNR for the 12 bit one was a typo , was referring to the 16 bit onboard dac in the M series card , which technically should ensure a clean input signal having atleast 90 db .
The info you have given helps a lot , i suspect the conditions inside the pc might be causing it , also i am driving the analog output from the card at almost its limits of 2.5 MS/s , the sample rate specification for the card on the data sheet says 2.8 MS/s , also i notice the settling time requirement for the outputs is 3 us which i suspect will put the onboard DAC under quite a load.
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Problem with distortion with DAQ Generating Sine wave

Hello,
I have a little problem with my VI who is made for driving a biphased stepper motor:
When I change dynamically the output frequency of my DAQ Generaor, I have some weird effect (see picture). It happend progressivelly like this :
(the start frequency doesn't matter)
95Hz - nothing
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Thank you in advance
Attachments:
Sub_Mesure1.vi ‏238 KB

Hello Mike,
I use 2 simulate signal setting in sine : see Capture2.png
and both DAQ Gen and Acq : Capture3.png / Capture4.png
Attachments:
Capture2.PNG ‏39 KB
Capture3.PNG ‏70 KB
Capture4.PNG ‏73 KB

Generating sawtooth in Analog Output

Dear Mr.
I am programinning in labview and I would like to generate from my DaqPad 6020E sawtooth signal. I have a problem becouse I can generate virtually but not in Analog Output. Please verify my program which is attached to the mail. If you can please write your simple program which generate sawtooth signal in analog Output. I was checked programs (examles) in ni.com but i can generate one. I know that AO works becouse i checked it sending sin (as trigonomethry sig) and there was no problem.
Best regards
Tomasz Olszewski
PS. If You speak Polish we can talk in Polish language.
Attachments:
ct03.vi ‏124 KB

Have you verified output in the Test Panels of the Measurement & Automation Explorer (MAX)? Simply wire analog output 0 to analog input 0. In the test panels, generate a sine wave on the analog output pin. If you can read in the signal on the Analog Input tab, then the board is operational and something is wrong in the code. Check the code to make sure you are referencing the correct device # and channels. Have a great day!

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Hi, I am attempting to start analog output based off a digital trigger (either PFIO, or a PXI line) I can do this easy in LabVIEW. However with the C API (through Python wrappers), the problem isthat when I call DAQmxBaseWriteAnalogF64, the write will always timeout as the acquisition has not been triggered. However, I cannot call this after the trigger occurs, as obviously that will be too late.
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Hi PatrickR,
You can review some of the text based NI DAQmx (ANSI C) code examples on generating an analog output using a digital start trigger. If you included/checked text-based support dusing your NI DAQmx driver installation, you can navigate to Windows Start>All Programs>National Instruments>NI DAQ>Teaxt-Based Code Support>ANSI C Examples>Analog Out>Generate Voltage>Mult Volt Updates-Int Clk-Dig Start. If you have any questions/concerns regarding the NI hardware.

Four analog outputs

I want to find a DAQ device which has four analog
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Jaejeen,
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2.- You can get a regular E Series Board, and you can use the two regular analog output channels, and the counters are other two analog output channels, but with the restriction to generate square waves only.
Hope this info is helpful.
L Aguila
Applications Engineer
National Instruments

How do I configure 128 channels of DIO and 128 channels of Analog output with the availability of 3 pci slots

I have only 3 slots of PCI or 4 slots of ISA bus, I want to configure with the minimum possible modules to attain 128 channels of DIO and 128 channels of analog output. This is inturn fed to the PCM (Pulse code Modulator). The cards will be placed in industrial PC.

Associate Engineer-Marketing,
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How to building a multi-channels analog output task in visual c++ 6.0 (without Measurement Studio)?

Hello!
I have a PCI 6251 card, and using DAQmx C function to generate a wavwform. (single channel ).
But, how to creating a multi-channels analog output task, and had a different frequence in each channels?
Thanks.

This is getting to be a common question!
The answer is, you can't.
If the rates have common factors, you can use a higher overall rate. The slower waveform will simply have extra points in it to make up for the higher update rate.
John Weeks
WaveMetrics, Inc.
Phone (503) 620-3001
Fax (503) 620-6754
www.wavemetrics.com

Synchronize a counter and Analog Output

Hello all,
I want my Analog Output generation and my Counter0 operations to start at the same time. Any ideas how to accomplish it.
I have tried to feed the output of another counter1 to the gate of counter0 as well as to the clock source of Analog Output (GPCTR1).
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Mili,
I think you'll have to experiment, but it might be possible to do both operations with the equipment you have. This would be relatively easy with an NI 660x counter/timer board.
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You can also search for many example programs/discussions at http://www.ni.com/support by searching in Option 3 for keywords like external, analog, output, and trigger.
Hope this helps.
Regards,
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National Instruments

CFP-AO-200 Analog output module (Error -33180) !!

Hello everyone
I'm using the cFP 1808 Bank along with other input modules like AI-111 and AI-110 ,I recently bought a AO-200 Module to output currents in the range from 4-20 mA ,I connected the module to the bank and updated the device from the MAX Software ,then I opened the Getting Started/Analog Output.vi from the examples in the Labview 2011 in order to test the card ,the VI returns an error with the code -33180 to me ,I don't know what's wrong ,but i tested the card with the MAX and wrote values to it successfully.
Can anybody tell me what's wrong with my VI
Thanks
Solved!
Go to Solution.

Post your VI so we can see what you are doing.
Did you read the error description for that error code?

6035E Analog Output problem

I have a 6035E with two analog outputs ("0" and "1"). Output 0
seems to work just fine, as do the analog inputs I've tried. The
problem is that output 1 does not. It only seems to give
-13V. Any thoughts? Thanks1

Please see this thread.
-Alan A.

Subtracting two waveforms, one aquired using DAQ analog voltage input, and the other one being internally generated

Hello NI Community,
I am new to LabView and was hoping someone might be able to help with a question I have. Right now, I am using a DAQ unit to sample an externally generated sinusoid and I would like to alter that signal by adding to it another signal that I could control using the front panel. Whenever I try to just connect the input with something like the sine waveform vi and put a subtraction sign between them it doesn't work (I get an empty waveform graph). To get around this, I have resorted to sending out a signal (through an analog output) and then reading the signal on the Daq, and then finally I add the two together. Doing it that way works, but it wastes two channels and I imagine there is a better way. I have attached my VI, and I labelled the location of interest "Where the Signals Get Subtracted", which is currently shown using the two inputs.
Thanks,
Leo

What a mess. I have no idea where you are trying to do the subtraction. Can you make a very small VI (one whose Block Diagram fits on a single screen) that shows what you are trying to do? Include the Sine Wave Generator, and you can include a "Black Box" that says "From DAQ". But thank you, at least, for posting code, not a picture.
Here's a suggestion that may help make things less messy -- do you know about the Diagram Cleanup tool? See the icons at the top? The right-most one looks like a broom next to a VI. Save your VI first (in case you don't like what it does), Select All (Ctrl-A), then click this button -- you may like the result.
Bob Schor

I am using an NI PCI 6024 E board device for an analog output application. Can I generate two independent waveforms, one on each analog output channel?

I am using an NI PCI 6024 E board device for an analog output application. Can I generate two independent waveforms, one on each analog output channel? In attach I send a example of my vi to control one chanel, but i need to control both but with diferent waveforms.
Is the vi correctly programed to this propose?

Yes you should be able to do that. look at the signal generation examples shipped with LabView
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To have different frequencies, you need to have say, on wave form with one cycle per buffer, and the other waveform have 2 cycles
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Generating 0 and 1 signal using labview Daq card

Hello,
I’m working on a Project on the On/Off control of a pneumatic cylinder via a 5/2 solenoid valve.
On State: Valve O/P 1 pushes cylinder İ/P 1
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1)      How can we enable the On/Off switching between the 2 O/P’s of the solenoid ?
2)      How can we enable the timing between On and Off States. ( On: 0-5 seconds Off: 0-5 seconds )
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Thanks a lot.

The digital out are a great place to start, however they are signal lines which means they don't drive a lot of current (~1mA). If your device isn't setup to accept digital signals you may have to use an external transistor to step up your amperage. See the link on here to get started
Labview can provide all the timing you need. I would search through the shipping examples (Help >> Find Examples) for digital output examples, there should be a bunch and one will probably work for you with just a little modification.
Jesse Dennis
Design Engineer
Erdos Miller

Using DAQ generate a 38kHz on an analog output on and off for ms using labVIEW

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